[Detection of Staphylococcus aureus resistant to methicillin (MRSA) by molecular biology (Cepheid GeneXpert IL, GeneOhm BD, Roche LightCycler, Hyplex Evigene I2A) versus screening by culture: Economic and practical strategy for the laboratory]. / Dépistage de Staphylococcus aureus résistant à la méthicilline (SARM) par biologie moléculaire (Cepheid GeneXpert IL, GeneOhm BD, LightCycler Roche, Hyplex Evigene I2A) versus dépistage par culture : stratégie économico-pratique pour le laboratoire.

OBJECTIVES: Patients admitted in cardiac surgery and cardiac ICU at the Clinic Saint-Gatien (Tours) are screened for MRSA at the entrance by nasal swab and culture on blood agar and selective chromogenic medium made by addition of cefoxitin: BBL CHROMagar MRSA-II BD (result obtained at Day +1). We wanted to assess the molecular biology techniques available to obtain a result at day 0 for the majority of patients and to define an economic and practical strategy for the laboratory. TECHNIQUES: We studied four molecular biology techniques: Cepheid GeneXpert (Cepheid) GeneOhm (BD), LightCycler (Roche) and Hyplex (I2A). Upon reception, nasal swabs were treated by culture, considered as reference, and one of the techniques of molecular biology, according to the manufacturer's notice. We conducted four studies between April 2008 and February 2009 to obtain a significant sample for each of them. METHODS: By screening we mean a method that allows us to exclude MRSA carriage for patients waiting for surgery, and not to change patient management: for example, lack of isolation measures specific to entrance, no modification of antibiotic prophylaxis during surgery and no isolation measures in the immediate postoperative period. RESULTS: The criteria we considered for this evaluation were: (1) technician time: time to perform one or a series of sample(s) n=10 or more (about 2h for all techniques except GeneXpert 75min), level of skilled competences (no specific training for GeneXpert); (2) results: turnaround time (all molecular biology techniques), ease of reading and results interpretations (no specialized training required for GeneXpert), failure or not (12% of failure of internal controls for GeneOhm); (3) economic: cost for one or a series of sample(s) (n=10 or more), if we considered X as the reference culture cost (10 X Hyplex and LightCycler, 20 X and 40 X for GeneXpert GeneOhm); (4) NPV: 100% for GeneXpert and LightCycler. CONCLUSION: At same sensitivity, no technique, including culture, can solve alone our problem, which is: (1) get results at day 0 for batch of samples (n<10): all molecular biology techniques; (2) beyond 10 samples: LightCycler (Roche) automated or Hyplex (I2A) manual; (3) when the result at day 1 is sufficient, the use of chromogenic agar with a reading of less than 18h as BBL CHROMagar MRSA II (BD) remains the most economical; (4) to be sure that a patient admitted at Day 0, even at night's emergency, is not carrier of MRSA: only Cepheid GeneXpert technology (IL). Furthermore, Cepheid GeneXpert (IL) allows performing several tests in parallel. The rapidity of this system can help control the transmission and make better use of antibiotics.

[1997-2007, 10 years of monitoring the evolution of resistance of Streptococcus pneumoniae to antibiotics in the region Centre; review of the Pneumococcus network]. / 1997-2007, dix ans de suivi de l'évolution de la résistance de Streptococcus pneumoniae aux antibiotiques en région Centre; bilan de l'observatoire du pneumocoque.

Regional pneumococcal observatories in region Centre, created in 1997, participate with the others pneumococcal observatories alongside the National Reference Center for Pneumococci and the Institut de Veille Sanitaire at the monitoring of the evolution of resistance of pneumococci to antibiotics in France. Between 1997 and 2007, 2427 strains of Streptococcus pneumoniae were isolated in part from cerebrospinal fluids, blood and middle ear fluid, from children and adults. The prevalence of pneumococci with a decreased susceptibility to penicillin (PDSP) decreased strongly in region Centre: 56.8 % in 2001, 39.6 % en 2007. These data are similar to the French national data over the same period.

How to: accreditation of blood cultures' proceedings. A clinical microbiology approach for adding value to patient care.

BACKGROUND: Quality assurance and quality management are driving forces for controlling blood culture best practices but should not be disconnected from the end-point target, i.e. patient value. AIMS: This article is intended to help microbiologists implement blood culture accreditation that is actually beneficial to patient management. SOURCES: Experience from a nationwide taskforce for promoting quality assurance and competence in clinical microbiology laboratories, guidelines on blood culture. CONTENT: Experience in blood culture accreditation according to International standard ISO 15189 standards is provided in this review, with a particular focus on critical points that are specific to blood culture (e.g. excluding strain identification or antimicrobial susceptibility testing). Blood culture test method verification is based on risk analysis, and evaluation of the test method's performance is based on the literature review and suppliers' data. In addition, blood culture performance relies largely on the quality of its pre-analytical phase, and the test method should be monitored based on key performance indicators such as the volume of blood cultured, the contamination rate and time to transportation. Other critical key indicators include the rate of false-positive signals, the rate of positive blood cultures, the ecology associated with positive results, and the timely communication of the results to the ward during the post-analytical phase. Finally, a critical analysis of quality controls and of the tools needed to improve blood culture monitoring in the future is provided. IMPLICATION: Appropriate quality assurance should focus on patient value rather than technical details to provide an appropriate clinical service.

Localization of the oxidative defect in phytanic acid degradation in patients with Refsum's disease.

The rate of oxidation of phytanic acid-U-(14)C to (14)CO(2) in three patients with Refsum's disease was less than 5% of that found in normal volunteers. In contrast, the rate of oxidation of alpha-hydroxyphytanic acid-U-(14)C and of pristanic acid-U-(14)C to (14)CO(2), studied in two patients, while somewhat less than that in normal controls, was not grossly impaired. These studies support the conclusion that the defect in phytanic acid oxidation in Refsum's disease is located in the first step of phytanic acid degradation, that is, in the alpha oxidation step leading to formation of alpha-hydroxyphytanic acid. The initial rate of disappearance of plasma free fatty acid radioactivity after intravenous injection of phytanic acid-U-(14)C (t(1/2) = 5.9 min) was slower than that seen with pristanic acid-U-(14)C (t(1/2) = 2.7 min) or palmitic acid-1-(14)C (t(1/2) = 2.5 min). There were no differences between patients and normal controls in these initial rates of free fatty acid disappearance for any of the three substrates tested. There was no detectable lipid radioactivity found in the plasma 7 days after the injection of palmitic acid-1-(14)C or pristanic acid-U-(14)C in either patients or controls. After injection of phytanic acid-U-(14)C, however, the two patients showed only a very slow decline in plasma lipid radioactivity (estimated t(1/2) = 35 days), in contrast to the normals who had no detectable radioactivity after 2 days. Incorporation of radioactivity from phytanic acid-U-(14)C into the major lipid ester classes of plasma was studied in one of the patients; triglycerides accounted for by far the largest fraction of the total present between 1 and 4 hr.

[Evaluation of Clinitek in the screening and optimisation of the diagnosis of urinary tract infection]. / Evaluation du Clinitek dans le dépistage et l'optimisation du diagnostic de l'infection urinaire.

A study was conducted to compare the interest of using Clinitek and leucocytes esterase, blood, nitrites strip Multistix-8 SG (Ames-Bayer Diagnostics) with conventional method (dilution of urine in agar plate) and with automated system (Autobac) as a screening procedure to detect significant bacteriuria. The results are expressed in terms of sensitivity, specificity, predictive value of a negative and positive test. A total of 1303 urine samples were tested of which 730 (56%) were founded negative with Clinitek or conventional urine analysis (Se = 83.6%; VPN = 89.6%). Criteria for urinary tract infection were present for 193 samples (14.8%), the predictive value of a negative test for leucocytes, blood or nitrites (99.6%) justifies the use of Clinitek for economical screening of urine. Overall agreement is higher with the results or Clinitek (in few seconds) than with the Autobac (in 4-5 hours) when compared to the conventional method. The authors propose Clinitek as an effective method for screening and optimised urine analysis for urinary tract infection.

[Routine determination of Neisseria gonorrhoeae susceptibility to antibiotics by a disk diffusion method (author's transl)]. / Détermination en routine de la sensibilité de Neisseria gonorrhoeae aux antibiotiques par und méthode de diffusion en milieu gélosé.

The susceptibility of 137 isolates of Neisseria gonorrhoeae to eleven antibiotics has been determined by a disk diffusion method. For nine antibiotics (penicillin G, ampicillin, amoxicillin, cefazolin, cefoxitin, tetracycline, minocycline, erythromycin and chloramphenicol) the results were found to be similar to those of fast growing aerobic bacteria antibiogram procedures. The correlation between diameter of inhibition measured with chocolate agar 1 p. cent polyvitex BioMérieux and minimum inhibitory concentrations determined by an agar dilution procedure with GC medium 1 p. cent haemoglobin, 1 p. cent supplement B Difco was good : coefficients ranging from r = 0,78 for penicillin G to r = 0,60 for minocycline. Less satisfactory results were found if chocolate agar 1 p. cent polyvitex was substituted by Gono-Meningo medium IPP. The technique described could be used for clinical purposes and epidemiologic survey.

[Brucella vaccination in professionally exposed subjects. Prospective study]. / Vaccination brucellique en milieu professionnel exposé. Etude prospective.

This prospective phase IV study on cohort concerns a vaccine made of the phenol-insoluble fraction of Brucella abortus biotype 1 (B19 strain). Three hundred and three professionally exposed subjects entered the study; 161 out of 182 subjects (88.5 percent) with negative response to an intradermal test for detection of previous contamination accepted to be vaccinated. Booster injections were given 18 and 36 months after vaccination. Local pain was observed after 45.2 percent of injections and moderate systemic reactions after 5 percent of injections. Seropositivity after primary vaccination reached 80 percent. The booster injection, justified by a major decrease of this rate after 18 months, gave exactly the same response of the thymo-independent type. This vaccinal schedule did not result in detectable hypersensitivity. The clinical effectiveness of the vaccine could not be evaluated accurately because of the insufficient number of subjects. The possibility of subclinical infection in vaccinated subjects calls for wider comparative studies of vaccinated versus non-vaccinated subjects.

[Postoperative infectious risk in traumatic bone surgery and protocol for antibiotic therapy]. / Risque infectieux post-opératoire en chirurgie osseuse traumatique et protocole d'antibiothérapie.

Eleven hundred and sixty eight traumatic cases have been operated on under constant conditions in a conventional operating room with filtered air and positive pressure using absolute filters of 99.999 efficiency. Two hundred and five were submitted to post-operative prophylactic administration of Cephalosporin (Cefazolin) for 2 days. The overall results showed 0.6 p. 100 of infection but 4 cases of severe sepsis were seen in the group of patients who had received prophylactic antibiotics. The authors have compared these results with those obtained during the previous period when the operating room was less modern. They conclude that this factor is of paramount importance. On the other hand, they have observed 2.1 p. 100 of contaminated drains without subsequent infection. They are concerned at the increase of gram-negative organisms resistant to Cefazolin (60 p. 100) and of Staphylococci resistant to Methicillin (30 p. 100). They conclude that the peroperative flash technique of the administration of Penicillin M is worthwhile.

[Human brucellosis in Benin: results of a serological survey among exposed workers]. / La brucellose humaine au Bénin: résultats d'une enquête sérologique chez des travailleurs exposés.

A serological survey was carried out in Bénin in order to assess the rate of brucellosis infection among exposed workers (workers in slaughtering-houses and breeders). 221 sera were tested with rose Bengale test, Wright sero-agglutination test, indirect immunofluorescence test and counter-immuno electrophoresis (brucelline). The percentage of positive sera among exposed workers is 17,7%. The rose Bengale and immunofluorescence tests combination permits complete detection of positive sera. These results suggest the existence of human brucellosis in Bénin and shows the necessity of a national control programme adapted to the socio-economic problems of this country.